Wi-Fi devices can offer all kinds of services. These may be services such as video rendering, audio rendering, printing, using a USB device such as a keyboard or a mouse over Wi-Fi, etc. Wi-Fi devices can ‘advertise’ these services over Wi-Fi, such that it is possible for other devices with a Wi-Fi radio to see what Wi-Fi services are available in their vicinity. A Wi-Fi device may also ask (probe') another Wi-Fi device about which Wi-Fi services it has to offer. Wi-Fi offers various ways to do such pre-association discovery.
Wireless docking in a system having a host device and dockees may be based on using a Wi-Fi (as described in IEEE802.11) based wireless docking station. The wireless docking station may be a wireless docking host (called WDH, or host) that enables a mobile device (called MD, or dockee) to access to a set of peripherals locally attached through a wire or wirelessly connected to the host device (such as USB mouse, HDMI display, Bluetooth headset) through a set of general message exchange protocols over a wireless link (e.g. Wi-Fi). A host coupled together with one or more wired or wireless peripherals is called a wireless docking environment. A host may also be a further mobile device having available one or more services for a dockee. Wireless docking is known, for example, from WO 2012/117306A1. A wireless docking station enables a wireless secured communication between at least one slave device and a master device.
The wireless docking host may provide information about its presence through a Wi-Fi beacon that dockees can use to select and initiate connections with a chosen host. Alternatively, Near Field Communication (NFC) tags associated with the host or other out of band means (such as using the communications interface of a wireless power system) may be used to communicate with a host to dock with. Using NFC for out-of-band device discovery is known, e.g., from chapter 3.1.2.7 of the Wi-Fi Peer-to-Peer (P2P) Technical Specification DRAFT v1.3.32, available from the Wi-Fi Alliance, Technical Committee P2P Task Group, via http://www.wi-fi.org/specifications.php or the document Wi-Fi Protected Setup pairing with NFC, available on http://msdn.microsoft.com/en-us/library/windows/hardware/dn481543%28v=vs.85%29.aspx, called Wi-Fi P2P standard in this document. Also, out-of-band means different from the main wireless communication radio band. For example, one speaks about an out-of-band channel, meaning a communication method that is of a different kind, e.g. NFC versus Wi-Fi.
Document US2013/0029596 describes pairing of wireless (BLUETOOTH) devices using data exchanged in an out-of-band (NFC) channel. Two devices are determined to be within near field communication (NFC) range of each other, and pairing information for a service is conveyed over the out-of-band channel. The conveying of the pairing information can require the first device to request at least one desired service and to provide a device ID. In response, the second device can, via the out-of-band channel, either deny the request or convey resource use parameters for the desired service and an ID for the second device. Pairing the two devices can use the resource use parameters.
Document WO2013/111537 discloses a communication system of a camera and a printer. The devices may communicate in a first mode (NFC) or in a second mode (Wi-Fi P2P). Startup in a first mode and handover between both modes is described.
Document Wi-Fi alliance “Wi-Fi Simple Configuration Technical Specification” v2.0.2 describes in section 10 “NFC Out-of-Band Interface Specification” using NFC as an out-of-band channel for Wi-Fi Simple Configuration. A password token or configuration token defining a WLAN configuration may be exchanged via NFC.
Document US2011/0210820 describes a system for simply and securely pairing multiple Bluetooth or other wireless electronic devices in a network. Multiple Near Field Communication (NFC) read-only tags are places in a vehicle or other defined space, such that users of NFC-enabled electronic devices can pass their device near one of the NFC tags, which then transfers encryption key data to the user's device, allowing that device to be automatically joined to a small, secure wireless network.
Document US 2011/0275316 describes a communication system that uses near-field communication in out-of-band initialization for connection setup for device-to-device communication.